That's super surprising that Ijin was completely caught off guard. A whole decade of being a child mercenary and he gets actually hit by a car that couldn't have been going too fast. Too fast and it would have been super loud and noticeable. Too slow and it's easily dodge-able.
Well, at least this way he'll get to know Yuna more. Will be interesting if he also gains the trust of her bodyguard (if you can even call him that) if they work together to retrieve Yuna and Dayun.